U.S. patent number 4,043,504 [Application Number 05/665,294] was granted by the patent office on 1977-08-23 for staple cartridge and feed means for use with a surgical stapling instrument.
This patent grant is currently assigned to Senco Products, Inc.. Invention is credited to J. Charles Hueil, Robert G. Rothfuss.
United States Patent |
4,043,504 |
Hueil , et al. |
August 23, 1977 |
Staple cartridge and feed means for use with a surgical stapling
instrument
Abstract
A staple cartridge and feed means for use with a surgical
stapling instrument of the type having an anvil about which a
staple is formed during emplacement thereof in the skin or fascia
of a patient. The cartridge comprises a body having a vertical
staple feeding track adapted to hold a stack of staples and a
separate vertical staple forming track with a staple former
reciprocable therein by the surgical stapling instrument. The
staple forming track and the staple feeding track are in parallel
relationship separated by a divider wall. A window, defined by the
cartridge body and the divider wall, provides a horizontal path
between the staple feeding track and the staple forming track and
is so sized as to permit the passage therethrough of a single
staple from the bottom of the staple stack. Horizontal feeder means
normally prevent passage of the bottommost staple from the stack
through the window into the staple driving track. The horizontal
feeder means, actuable by the surgical stapling instrument,
positively shifts the bottommost staple of the stack from the
staple feeding track horizontally through the window to the staple
forming track and cooperates with retainer springs to hold a
shifted staple in position in the staple forming track to be
implanted and formed about the anvil by the staple former.
Inventors: |
Hueil; J. Charles (Loveland,
OH), Rothfuss; Robert G. (Bellevue, KY) |
Assignee: |
Senco Products, Inc.
(Cincinnati, OH)
|
Family
ID: |
24669531 |
Appl.
No.: |
05/665,294 |
Filed: |
March 9, 1976 |
Current U.S.
Class: |
227/116; 227/19;
227/120 |
Current CPC
Class: |
B25C
5/1603 (20130101); A61B 17/0684 (20130101) |
Current International
Class: |
B25C
5/16 (20060101); A61B 17/068 (20060101); B25C
5/00 (20060101); B25C 005/02 () |
Field of
Search: |
;227/19,85,95,114,116,120,126 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Custer, Jr.; Granville Y.
Attorney, Agent or Firm: Melville, Strasser, Foster &
Hoffman
Claims
The embodiments of the invention in which an exclusive property or
privilege is claimed are defined as follows:
1. A staple cartridge for use with a stapling instrument, said
cartridge comprising a body having therein a staple forming track
with a reciprocable staple former therein actuable by said
instrument, a separate and distinct parallel staple feeding track
for a stack of staples, a passage between said staple feeding and
forming tracks so sized as to permit the passage therethrough of
one staple at a time from said staple feeding track to said staple
forming track, means actuable by said instrument to shift one
staple at a time from said staple feeding track through said
passage into said staple forming track, said staple shifting means
closing said passage when a staple is not being shifted
therethrough by said staple shifting means, and means to maintain a
staple shifted into said staple forming track in proper position
therein to be acted upon by said staple former.
2. The structure claimed in claim 1 including means separate and
distinct from said staple shifting means to urge the bottommost
staple of a stack thereof in said staple feeding track into
position to be shifted through said passage by said staple shifting
means.
3. A staple cartridge for use with and affixable to a surgical
stapling instrument of the type having an anvil about which a
staple is formed during emplacement thereof in the skin or fascia
of a patient, said cartridge comprising a body having therewithin a
vertical staple feeding track with closed upper and lower ends and
a separate, parallel, vertical staple forming track with a closed
upper end and an open lower end adapted to be adjacent said
surgical stapling instrument anvil when said cartridge is affixed
to said instrument, a staple former shiftable within said staple
forming track by said instrument between a retracted position and
an extended position wherein it forms a staple about said anvil, a
stack of staples located within said vertical staple feeding track,
a horizontal passage extending laterally from said vertical staple
feeding track adjacent said lower end thereof to said vertical
staple forming track and being so sized as to permit the shifting
therethrough of only one staple at a time from said vertical staple
feeding track to said vertical staple forming track, horizontal
feeder means actuable by said instrument to shift the bottommost
staple of said stack from said staple feeding track horizontally
through said passage into said vertical staple forming track, said
horizontal feeder means closing said passage when a staple is not
being shifted therethrough by said horizontal feeder means and
means to maintain a staple shifted into said vertical staple
forming track in proper position therein to be engaged by said
staple former and formed about said instrument anvil when said
staple former is shifted by said instrument from said retracted to
said extended position.
4. The structure claimed in claim 3 including staple ejection
spring means within said staple cartridge to push a formed staple
off of said anvil.
5. The structure claimed in claim 4 wherein said staple ejection
spring means has a pair of legs normally extending across said
staple forming track and having downwardly depending tabs normally
lying just above said anvil at the free end thereof, said staple
ejection spring legs and tabs being shiftable to a retracted
position out of said staple forming track by a staple and said
staple former during a staple forming operation whereby said staple
ejection spring legs and tabs will spring back to their normal
position upon formation of said staple and return of said staple
former to said retracted position removing said formed staple from
said anvil.
6. The structure claimed in claim 3 including means separate and
distinct from said horizontal feeder means within said staple
feeding track to urge said stack of staples toward said lower end
of said staple feeding track.
7. The structure claimed in claim 6 wherein said means to urge said
stack of staples toward said lower end of said staple feeding track
comprises a sinuous spring the upper end of which abuts said closed
upper end of said staple feeding track and the lower end of which
abuts said stack of staples.
8. The structure claimed in claim 3 wherein said body is made up of
three elements joined together in face-to-face abutting
relationship, said elements comprising a staple former housing, a
horizontal feeder housing and an intermediate staple housing, said
staple formed housing comprising an elongated substantially
rectangular element having on its side facing said staple housing a
longitudinally extending depression comprising said staple forming
track, said intermediate staple housing comprising a substantially
rectangular element having on its side facing said staple former
housing a longitudinally extending depression comprising said
staple feeding track and terminating at one end in a shoulder on
said staple housing forming said lower end of said staple track, a
thin, substantially rectangular divider wall mounted on said staple
housing and separating said staple feeding track from said staple
forming track when said staple housing and said staple former
housing are joined together in said abutting relationship, said
divider wall having a lower edge so configured and so spaced from
said staple housing shoulder as to define therewith said horizontal
passage, said staple housing having a transverse opening therein
opposite said passage, said horizontal feeder housing comprising a
substantially rectangular element having a longitudinally extending
resilient tine comprising said horizontal feeder, said horizontal
feeder having a free end terminating in a laterally extending
pusher portion freely receivable through said opening in said
staple housing when said staple housing and said horizontal feeder
housing are joined together in said abutting relationship, said
horizontal feeder being shiftable between a normal position wherein
said pusher portion extends through said opening in said staple
housing, through said staple feeding track and into said passage
and a retracted position wherein said pusher portion is withdrawn
from said passage and said staple forming track.
9. The structure claimed in claim 8 wherein said staple former
housing, said horizontal feeder housing and said intermediate
staple housing are removably joined together whereby said staple
cartridge is refillable and reusable.
10. The structure claimed in claim 9 wherein said staple former
housing, said horizontal feeder housing and said intermediate
staple housing are made of stainless steel.
11. The structure claimed in claim 8 wherein said cartridge is
disposable, said staple former housing, said horizontal feeder
housing and said intermediate staple housing being permanently
joined together.
12. The structure claimed in claim 11 wherein said staple former
housing, said horizontal feeder housing and said intermediate
staple housing are formed of plastic material.
13. The structure claimed in claim 8 including a pair of staple
retainer springs, said staple former housing having a depression
within said staple former track, said retainer springs being
affixed at on end to said staple former housing within said
depression, said retainer springs having a normal position wherein
their free ends extend across said staple former track and abut
said divider wall and staple housing spanning and additionally
closing said passage, said retainer springs being partially
deformable by a staple entering said staple former track under the
influence of said pusher portion of said horizontal feeder and
further deformable to a position wholly within said retainer spring
depression by said staple former, said means to retain a staple in
proper position within said staple former track comprising said
retainer springs and said pusher portion of said horizontal
feeder.
14. The structure claimed in claim 8 including an integral,
resilient detainer tine on said staple former housing to normally
engage and retain said staple former in its retracted position.
15. The structure claimed in claim 8 including a longitudinal
channel in that side of said horizontal feeder housing facing said
staple housing, a horizontal feeder actuator slidably mounted in
said channel, said actuator comprising an elongated member having
an upper end and a lower end, said horizontal feeder having a cam
surface thereon, said actuator being vertically shiftable within
said horizontal feeder housing channel by said instrument between a
normal retracted position and an extended position wherein said
lower end of said actuator engages said cam surface on said
horizontal feeder to shift said horizontal feeder to said retracted
position thereof.
16. The structure claimed in claim 15 wherein said actuator has at
said upper end an integral laterally extending driving eyelet, said
eyelet extending through a notch in said staple housing and an
elongated hole in said staple former housing whereby said actuator
driving eyelet may be engaged by a vertically shiftable drive pin
of said surgical stapling instrument.
17. The structure claimed in claim 8 wherein said staple former has
an integral laterally extending driving eyelet, said eyelet
extending through an elongated hole in said staple former housing
whereby said staple former driving eyelet may be engaged by a
vertically shiftable drive pin of said surgical stapling
instrument.
Description
BACKGROUND OF THE INVENTION
I. Field of the Invention
The invention relates to a staple cartridge and feed means and more
particularly to a staple cartridge well suited for use with a
surgical stapling instrument.
II. Description of the Prior Art
While the staple cartridge and feed means of the present invention
is capable of many applications, it will, for purposes of an
exemplary showing, be described in terms of its use with a surgical
stapling instrument for which it is particularly well adapted.
Recently, surgeons have come more and more to the use of staples,
rather than conventional thread sutures, for closing wounds or
incisions in the skin and fascia of a patient. This trend is due
largely to the fact that the use of staples is a far easier
procedure and, of even greater importance, is very much faster.
This substantially reduces the time required for suturing and the
length of time the patient must be maintained under
anaesthesia.
Prior art workers have developed various types of surgical stapling
instruments and staple cartridges for use therewith. Of particular
concern has been the staple feed means within a cartridge and
numerous approaches have been taken by prior art workers. For
example, cartridges have been devised wherein the staple feed means
comprises a pair of staple-advancing screws. The staples are
retained by and advanced by the threads of the pair of
staple-advancing screws and it will be appreciated that the pair of
screws must be turned very precisely to prevent jamming of the
staples within the cartridge. As a consequence, complex gear means
or cam means are required to turn the staple-advancing screws.
Examples of such cartridges are taught in U.S. Pat. Nos. 3,618,842
and 3,643,851.
Another approach is taught in U.S. Pat. No. 3,638,847 wherein the
cartridge is provided with a stationary sawtooth staple-retaining
member and a reciprocating sawtooth staple advancing member adapted
to cooperate with the staple former or pusher. U.S. Pat. No.
3,650,453; 3,717,294 and 3,837,555 teach yet another approach
wherein a plurality of staples are guided and advanced by a
continuous belt adapted for rotation within the cartridge. The belt
and staples mounted thereon are advanced by the action of the
staple former or by the inter-action of the staple former and the
forwardmost staple.
It will be evident from the foregoing that prior art staple
cartridge and feed means have been complex in construction and
difficult and expensive to manufacture. The complexity of the feed
means has had a direct bearing on the reliability of prior art
cartridges, it being understood by one skilled in the art that once
a staple has jammed within the cartridge, the cartridge and its
remaining staples cannot be further used. The complexity of prior
art staple cartridge and feed means has been reflected in the
complexity and expense of the surgical stapling instruments with
which the cartridges are used. The use of complicated gear means or
the staple former itself to advance the staples within the
cartridge has required considerable power from the surgical
stapling instrument.
The present invention is based upon the discovery that a very much
simpler, less expensive, and more reliable staple cartridge can be
achieved by providing a vertical staple feeding track to
accommodate a plurality of staples and spring means to advance the
staples therein; a separate vertical, parallel staple forming track
housing a reciprocating staple former; a window providing a
horizontal passage between the two tracks and sized to permit a
single staple to pass therethrough; means to normally maintain the
staples within the staple feeding track; positive means to
selectively shift a single staple from the staple feeding track
through the window to the staple forming track and means to
maintain such a shifted staple in proper position within the staple
forming track for engagement by the staple former. The provision of
vertical staple feed means and horizontal staple feed means which
are independent of each other and independent of the staple former
results in an arrangement in which the staples are far less likely
to become jammed. In this arrangement the staple feeding portion of
the cartridge cycle is completed before the start of the staple
forming portion of the cartridge cycle.
The cartridge of the present invention requires less power from the
surgical staple instrument to operate it. The staple feeding means
is extremely reliable with the result that staples can be
consistently and accurately formed about the anvil of the surgical
stapling instrument.
SUMMARY OF THE INVENTION
The staple cartridge and feed means of the present invention
comprises an elongated body having separate, parallel, vertical
staple feeding and staple forming tracks. These tracks are
separated from each other by a thin divider wall. The staple
feeding track is adapted to accommodate a stack of staples and a
feeder spring to advance the staples along the staple feeding
track. The staple forming track has a staple former slidably
mounted therein and shiftable between retracted and extended
positions by the surgical stapling instrument with which the
cartridge is used.
A window defined by the cartridge body and the divider wall
provides a horizontal passage between the staple feeding track and
the staple forming track. This window is so sized and configured as
to permit the passage therethrough of only one staple at a time
(i.e. the bottommost staple of the staple stack).
A positive horizontal feeder means, actuable by the surgical
stapling instrument, is provided to shift the bottommost staple of
the staple stack through the window and into the staple forming
track. Retainer springs are located in the staple forming track.
These retainer springs cooperate with the window and the horizontal
feeder to permit the passage of only single staples through the
window. The positive horizontal feeder means and the window
cooperate to retain the remainder of the staple supply within the
staple feeding track. The retainer springs additionally cooperate
with the horizontal feeder and staple former to maintain a staple,
having been shifted through the window, in proper position within
the staple forming track for engagement by the staple former. The
cartridge may also be provided with a staple ejection spring to
assist in removal of a formed staple from the anvil of the surgical
stapling instrument.
As will be described hereinafter, the staple cartridge and feed
means of the present invention may be so dimensioned as to
accommodate staples of any desired size and suitable configuration
and can be made to be disposable or refillable and reusable.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the staple cartridge and feed means
of the present invention.
FIG. 2 is a front elevational view of a staple usable in the
cartridge of the present invention.
FIG. 3 is a semi-diagrammatic side elevational view of a surgical
stapling instrument with the cartridge mounted thereon.
FIG. 4 is an exploded perspective view of the staple cartridge and
feed means of the present invention illustrating the components
thereof.
FIG. 5 is a plan view of that side of the staple former housing not
shown in FIG. 4.
FIG. 6 is a cross-sectional view taken along section line 6--6 of
FIG. 1 and illustrates the components of the staple cartridge and
feed means in their normal, at rest positions.
FIG. 7 is a cross-sectional view similar to FIG. 6 with the
components of the staple cartridge and feed means in their
respective positions when the horizontal feeder is in its most
retracted position.
FIG. 8 is a cross-sectional view similar to FIGS. 6 and 7 with the
components of the staple cartridge and feed means in their
respective positions immediately after the horizontal feeding of a
staple through the window has been accomplished.
FIG. 9 is a cross-sectional view similar to FIGS. 6 through 8 with
the components of the staple cartridge and feed means in their
respective positions when the staple has been formed about the
anvil of the surgical stapling instrument.
FIG. 10 is a fragmentary cross-sectional view taken along section
line 10--10 of FIG. 6.
FIG. 11 is a fragmentary cross-sectional view taken along section
line 11--11 of FIG. 7. FIG. 12 is a fragmentary cross-sectional
view taken along section line 12--12 of FIG. 8.
FIG. 13 is a fragmentary cross-sectional view taken along section
line 13--13 of FIG. 9.
FIG. 14 is a fragmentary elevational view of the staple
housing.
FIG. 15 is an elevational view of the staple ejection spring.
FIG. 16 is an end view of the staple ejection spring of FIG. 15 as
seen from the bottom thereof.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a perspective view of the staple cartridge and feed means
of the present invention. The cartridge is generally indicated at 1
and comprises an elongated, substantially rectangular body,
generally indicated at 2. The bottom end of the cartridge is
bifurcated, as shown at 3, to enable it to straddle the anvil 4 of
the surgical instrument (see FIGS. 6 through 13). The staple
cartridge and feed means of the present invention may be configured
and dimensioned to accept various sizes and types of staples. While
not intended to constitute a limitation on the present invention,
for purposes of an exemplary showing the cartridge is illustrated
and described as housing surgical staples of the type taught in the
co-pending application Ser. No. 858,804, filed June 11, 1975 in the
name of Robert G. Rothfuss and entitled: SURGICAL STAPLE.
A staple of the type taught in this co-pending application is
illustrated in FIG. 2 and is generally indicated at 5. The staple
comprises a crown portion 6 having legs 7 and 8. Legs 7 and 8 have
first upwardly and outwardly sloping portions 7a and 8a terminating
in second, downwardly and outwardly sloping portions 7b and 8b. The
staple points 7c and 8c are formed by diagonal cuts across the leg
ends. As is explained in the above identified co-pending
application the cuts forming points 7c and 8c are so arranged as to
be perpendicular to the upper surface of the surgical stapling
instrument anvil 4 and the skin or fascia of the patient, whereby
the staple penetrates the skin or fascia during emplacement without
the tendency to slide therealong. The configuration of this staple
not only affords greater skin gathering during emplacement, but
also facilitates stacking of the staples in the cartridge staple
feeding track, allowing more staples per linear inch of staple
feeding track.
FIG. 3 illustrates in semi-diagrammatic fashion a surgical stapling
tool generally indicated at 9. The tool comprises a body 10 having
a nose portion 11, a handle portion 12 and an actuator or trigger
13. The cartridge 1 is shown in place on the nose 11 of the
instrument. The precise configuration and the operating
instrumentalities of the surgical stapling instrument do not
constitute limitations of the present invention. The device may be
fluid powered, mechanically actuated by trigger 13, or the like. It
will be understood by one skilled in the art that the anvil 4 of
the surgical instrument 9 is located at the free end of nose 11,
although not visible in FIG. 3.
For a better understanding of the staple cartridge and feeding
means of the present invention reference is now made to FIGS. 4 and
6 wherein like parts have been given like index numerals. The body
2 of the cartridge 1 of FIG. 1 is made up of three basic parts
between which all of the remaining parts are located. These basic
parts comprise a staple former housing 14, a staple housing 15 and
a horizontal feeder housing 16. The parts 14 through 16 may be made
of any suitable material approved for use in a surgical environment
and capable of withstanding sterilization procedures. While not so
limited, stainless steel may be used for parts 14 through 16,
particularly when the cartridge is intended to be refillable and
reusable. Under these circumstances, these parts may be joined
together by screws or other removable fastening means. When the
cartridge is intended to be disposable these parts are preferably
made of plastic or the like. The parts 14 through 16 lend
themselves well to be molded from a plastic material suitable for
surgical use. Under these circumstances the parts 14 through 16 may
be joined together by ultrasonic welding, gluing or the like.
The staple former housing 14 has a planar exterior surface. The
upper end of the staple former housing is of greater thickness than
the remainder thereof, forming a shoulder 17. A perforation 18 of
elongated configuration passes through the upper portion. The
intermediate portion of the staple former housing has a second
perforation 19 pssing therethrough. The perforation 19 is of
greater length than perforation 18. Yet another perforation 20
passes through the staple former housing and is of U-shaped
configuration defining an integral, resilient tine or foot 21 which
serves as a staple former detainer, as will be described
hereinafter. The bottommost end of the staple former housing has a
notch 22 within which the anvil 4 of the surgical stapling
instrument 9 is received and forming a part of notch 3 of FIG. 1.
Turning to FIG. 5, it will be noted that the interior surface of
that portion of the staple former housing 14 to the left of
shoulder 17 (as viewed in FIG. 5) comprises a planar, U-shaped
surface 23 surrounding a longitudinal depression 24 adapted to
receive the staple former 25 shown in broken lines. The depression
24 extends all the way to the bottom end of the staple former
housing 14 and constitutes the staple former track of the cartridge
within which the staple former 25 may shift between a fully
retracted position shown in FIG. 5 and a fully extended position
(shown in FIG. 13) wherein the bottom edge of the staple former 25
extends to a position sufficient to accomplish forming of a staple.
In the particular exemplary embodiment illustrated, the staple
former travels all the way to the bottom edge of the staple former
housing when in its fully extended position.
An additional depression 26 is located in the staple forming track
24 and is adapted to receive a pair of L-shaped retainer springs 27
and 27a which are staked, glued or otherwise appropriately attached
to the staple former housing 14. As is most clearly shown in FIG.
6, that portion of depression 26 receiving the long legs of
retainer springs 27 and 27a slopes downwardly and toward the
exterior surface of the staple former housing 14. The purpose for
this will be explained hereinafter. Retainer springs 27 and 27a are
also clearly shown in FIG. 4. If desired, retainer springs 27 and
27a may be formed as an integral one-piece structure.
Beneath springs 27 and 27a there is positioned and attached to
staple former housing 14 a staple ejection spring 28. Staple
ejection spring 28 is optional but its presence is preferred to
eject a formed staple from the anvil 4. Thus, staple ejection
spring 28 aids the disconnection of the surgical stapling tool 9
from a staple formed around its anvil 4 and into the skin of the
patient with a minimum of tramma to the patient.
Staple ejection spring 28 is most clearly shown in FIGS. 15 and 16
and is preferably made of roundwire spring tempered stainless steel
or the like. Staple ejection spring 28 is formed into a near
rectangle having a top 28a and sides 28b and 28c terminating in
inturned legs 28d and 28e with downwardly depending tabs 28f and
28g. As is evident from FIG. 16, legs 28d and 28e are bent slightly
out of the plane in which top 28a and sides 28b and 28c lie.
When staple ejection spring 28 is in its normal position (see FIG.
6) the spring legs 28d and 28c extend across the staple former
track 24 with spring tabs 28f and 28g being located just above the
top surface of anvil 4 at the free end of the anvil. Spring tab 28f
is shown in FIG. 6. The operation of staple ejection spring 28 will
be described hereinafter.
Turning again to FIG. 4 the staple former 25 constitutes a
substantially rectangular, planar element having an upstanding
driving eyelet 25a adapted to extend through the elongated
perforation 19 of the staple former housing 14 and to be engaged by
a drive pin 29 (shown in broken lines in FIGS. 6 through 9) of the
surgical stapling instrument 9. The bottommost edge of staple
former 25 has a notch 30 therein. The bottom corners of notch 30
are relieved as at 31 and 32. This configuration of the notch
enables the staple former 25 to form a staple about the surgical
stapling instrument anvil 4, as is illustrated in FIG. 13.
The staple housing 15 (FIGS. 4, 6 and 14) has a substantially
planar surface 15a facing in the direction of the horizontal feeder
housing 16. The upper end 33 of the staple housing 15 is of lesser
thickness than the remainder of the staple housing, forming a
shoulder 34. This upper end 33 is provided with an elongated,
U-shaped notch 35, the purpose of which will be described
hereinafter.
To the left of shoulder 34 (as viewed in FIG. 4) a planar surface
36 extends about three sides of a longitudinal depression 37 and a
pair of flanking shoulders 38 and 39. The elongated depression 37
constitutes the staple feeding track of the cartridge and is
intended to receive a stack (generally indicated at 40) of staples
5 and a sinuous staple advancing spring 41.
The bottom end of the staple feeding track 37 is defined by a
shoulder 42 having the same configuration as the underside of
portions 6, 7a and 8a of staple 5 (FIG. 2). The shoulder 42 is
flanked by a pair of clearance notches 43 and 44 which are, in
turn, flanked by shoulders 45 and 46, respectively. The bottommost
end of the staple housing is provided with a notch 47 (larger than
the notch 22 of the staple former housing 14 to permit a formed
staple to be removed from the anvil 4) constituting a part of notch
3 of FIG. 1.
A divider wall 48 is shown in FIG. 4 and comprises a substantially
rectangular, planar element. The lowermost end of divider wall 48
is provided with a pair of notches 49 and 50 defining bottom edge
surfaces 51, 52 and 53.
Divider wall 48 is intended to separate the staple feeding track 37
from the staple forming track 24. To this end, the divider wall 48
is so sized as to be supported on shoulders 38 and 39 of the staple
housing. When the staple former housing 14 and staple housing 15
are mated, staple former housing surface 23 will lie in abutting
relationship with staple housing surface 36 and will overlap and
maintain in place the divider wall 48. The shoulder 17 of staple
former housing 14 will lie in abutment with shoulder 34 of staple
housing 15, the shoulder 17 forming the upper end of the staple
feeding track 37. The upper end 54 of the divider wall 48 will lie
in abutment against shoulder 17 of the staple former housing 14.
The bottom end edges 51 and 52 of divider wall 48 will contact
shoulders 45 and 46, respectively of the staple housing 15. It will
be understood that in the assembly thus far described, when the
stack of staples 40 and the sinuous spring 41 are located in place
within the staple feeding track 37, the uppermost end 41a of the
sinuous spring will abut the shoulder 17 of the staple former
housing 14 and the lower end 41b of sinuous spring 41 will engage
the uppermost staple of the stack 40. The shoulder 42 of the staple
housing and lower edge 53 and notches 49 and 50 of divider wall 48
are, when the cartridge is assembled, separated from each other by
a distance slightly greater than the thickness of one staple. In
this way, the shoulder 42 of the staple housing and the lower end
of divider wall 48 form a horizontal passage or "window" through
which the lowermost staple of stack 40 may pass from staple feeding
track 37 to staple forming track 24 under the urging of a positive
horizontal feeder to be described hereinafter. This window is shown
at 55 in FIGS. 6 through 9.
The horizontal feeder housing 16 is illustrated in perspective in
FIG. 4 and comprises an elongated substantially rectangular
element. The exterior surface 56 of the horizontal feeder housing
16 is substantially planar, as shown in FIG. 6. The interior
surface 57 is also substantially planar having a longitudinally
extending depression 58 therein and a U-shaped opening 59 defining
an integral, resiliently biased tine, hereinafter referred to as
the horizontal feeder 60.
Horizontal feeder 60 has a normally planar portion 61 which
constitutes a continuation of the bottom surface of depression 58.
The planar portion 61 terminates in a wedge-shaped cam surface 62
and a pusher portion 63 the forward edge 63a of which corresponds
in shape to portions 6, 7a and 8a of staple 5 (see FIG. 2). It will
be understood that the staple housing 15 has, adjacent shoulder 42,
an opening therein permitting the pusher portion 63 of the
horizontal feeder to be freely shifted therethrough. This opening
is most clearly shown in FIG. 14 at 64. Finally, the horizontal
feeder housing 16 has at its lowermost end a notch 16a constituting
a part of notch 3 of FIG. 1.
FIG. 4 illustrates a horizontal feeder activator 65. Activator 65
comprises an elongated element terminating in a rounded nose 66 at
one end and a driving eyelet 67 at the other. Activator 65 is
adapted to lie in and be reciprocable in channel 58 of horizontal
feeder housing 16. Driving eyelet 67 extends through the notch 35
in the upper end of the staple housing 15 and through the elongated
opening 18 in the staple former housing 14, to be engaged by a
drive pin of the surgical stapling instrument 9. The drive pin is
illustrated in broken lines at 68 in FIGS. 6 through 9.
FIGS. 6 through 13 illustrate the staple cartridge and feed means
of the present invention in its fully assembled form and they
further illustrate its operation. Turning first to FIGS. 6 and 10,
the staple cartridge and feed means is shown in its normal, at rest
condition, mounted upon the surgical stapling instrument 9 (not
shown). The manner in which the cartridge is held in place on the
surgical stapling instrument 9 does not constitute a part of this
invention. The surgical stapling instrument anvil 4 is shown in
broken lines located within the notch 3 in the end of the cartridge
1. The drive pins 29 and 68 of the surgical stapling instrument 9
are shown located within driving eyelets 25a of staple former 25
and driving eyelet 67 of horizontal feed activator 65,
respectively.
Initially, the staple former 25 is in its fully retracted position
and is maintained there by the staple former detainer tine 21 of
staple former housing 14. A primary purpose of staple former
detainer line 21 is to assure that the staple former 25 remains in
its fully retracted position during shipping and handling. This, in
turn, assures that staple former 25 will be in proper position to
receive drive pin 29 during attachment of the cartridge 1 to the
surgical stapling instrument 9. The staple former detainer tine 21
also serves to hold staple former 25 in its uppermost position
during the lost motion sequence of drive pin 29.
It will be noted that the horizontal feeder activator 65 is
normally in its fully retracted position. As a consequence, when
the resiliently biased horizontal feeder 60 is in its normal
position, the pusher portion 63 thereof extends through opening 64
in staple housing 15, beneath the lowermost staple 5a of stack 40
and into window 55 with the forwardmost edge 63a of pusher portion
63 being coplanar with that surface of divider wall 48 adjacent
staple former 25. This effectively closes window 55 assuring that
none of the staples of the stack 40 passes therethrough. Finally,
in the normal at rest position of the cartridge 1, staple retainer
springs 27 and 27a abut divider wall 48 and staple housing 15 at
the region of window 55, forming another effective closure for the
window. This is illustrated in FIG. 10 and particularly in FIG. 6
wherein spring 27a is shown.
Turning to FIGS. 7 and 11, as the trigger 13 of surgical stapling
instrument 9 (FIG. 3) is actuated, drive pins 29 and 68 of the
surgical stapling instrument 9 are driven toward the forming anvil
4. Initial movement of drive pin 29 does not move staple former 25
since, as can be noted from FIG. 7, the diameter of driving eyelet
25a of staple former 25 is larger than the diameter of the stapling
instrument drive pin 29. Staple former detainer tine 21 retains
staple former 25 in its uppermost position.
Driving eyelet 67 of the horizontal feeder actuator 65 has an
internal diameter so sized as to just receive surgical stapling
instrument drive pin 68. As a consequence, initial movement of
drive pin 68 will cause the horizontal feeder activator 65 to shift
downwardly. Rounded nose 66 of the horizontal feeder activator 65
engages cam surface 62 of the horizontal feeder 60 causing the
feeder 60 to be deflected from its normal position and withdrawing
pusher portion 63 of the horizontal feeder from window 55 and
staple feeding track 37. This, in turn, permits the stack of
staples 40, under the influence of sinuous spring 41, to shift
vertically downwardly until the lowermost staple 5a of the stack 40
abuts shoulder 42 of staple housing 15. The bottommost staple 5a of
stack 40 is prevented from passing through window 55 by staple
retainer springs 27 and 27a. It will be noted in FIG. 7 that at
this stage of the staple cartridge and feed means cycle the
surgical stapling instrument drive pin 29 has contacted driving
eyelet 25a of staple former 25 and is about to begin downward
movement of staple former 25.
The next stage of the staple cartridge and feed means cycle is
illustrated in FIGS. 8 and 12. Once the components of the staple
cartridge and feed means have reached their positions illustrated
in FIG. 7, it will be noted from FIG. 8 that the direction of drive
pin 68 is rapidly reversed, quickly returning the horizontal feeder
activator 65 to its normal position. This causes resiliently biased
horizontal feeder 60 to return to its normal position. During the
return of the resiliently biased horizontal feeder 60 to its normal
position, its pusher portion 63 passes through staple feeding track
37 stripping the bottommost staple 5a from staple stack 40 and
transferring the bottommost staple 5a horizontally through window
55 and into staple forming track 24. As will be evident from FIG.
8, the movement of lowermost staple 5a into staple forming track 24
under the influence of pusher portion 63 of horizontal feeder 60
results in a slight deflection of staple retainer springs 27 and
27a into the depression 26 of the staple former housing 14. Staple
retainer springs 27 and 27a cooperate with pusher portion 63 of
horizontal feeder 60 to maintain staple 5a in a position part way
within staple forming track 24. It will further be noted from FIGS.
8 and 12 that staple former 25 has begun its downward movement past
staple former detainer tine 21 under the influence of the surgical
stapling instrument drive pin 29. Retainer springs 27 and 27a bias
the staple 5a against pusher portion 63. Staple former 25 pushes
springs 27 and 27a into depression 26 while horizontal feeder 60
urges staple 5a fully into forming track 24. Thus it will be noted
from FIGS. 8 and 12 that at this stage of the staple cartridge and
feed means cycle a single staple 5a has been selectively moved from
the bottom of the stack of staples 40 into a position within staple
forming track 24 below the staple former 25 where it is ready to be
formed by the staple former about surgical stapling instrument
anvil 4. The staple feeding portion of the cartridge cycle has been
accomplished and the staple forming portion of the cycle is ready
to begin.
Continued motion of surgical stapling instrument drive pin 29 will
cause staple 5a and thereafter staple former 25 to contact staple
ejection spring legs 28d and 28e. The slight downward slope of
these legs (see FIG. 15) will cause them and tabs 28f and 28g to be
bent away from the free end of anvil 4 to a retracted position out
of staple former track 24. Further downward motion of the staple
former will implant staple 5a in the skin or fascia of the patient
and form the staple about the surgical stapling instrument anvil 4.
At this point, the components of the staple cartridge and feed
means will be in the positions shown in FIGS. 9 and 13 with staple
former 25 maintaining staple ejection spring 28 in its retracted
position. As will be evident from FIG. 13, the relieved edges 31
and 32 of staple former 25 will ease the crown 6 of staple 5a into
the staple former notch 30 causing a bending of portions 7a and 8a
of staple 5a until staple 5a assumes the configuration illustrated
in FIG. 13.
Release of trigger 13 of the surgical stapling instrument 9 will
result in the return of drive pin 29 to its normal position,
returning staple former 25 to its uppermost position. This, in
turn, will free staple ejection spring 28 to return to its normal
position. In so doing, staple ejection spring tabs 28f and 28g will
contact formed staple 5a near the center of its crown and push the
staple off of anvil 4. It will be understood that when staple
ejection spring is held in its retracted position (FIG. 9), the
sides 28b and 28c thereof will be twisted in torsion spring fashion
so that they will tend to urge tabs 28f and 28g to their normal
positions. Once staple 5a is removed from anvil 4, all of the
components of the staple cartridge and feed means will then be in
their normal, at rest positions illustrated in FIG. 6 and the cycle
can thereafter be repeated.
As applied herein and in the claims, the terms "vertical" and
"horizontal" are used simply to define the relative positions of
the components of the staple cartridge 1 and its feed means. During
use, it will be understood by one skilled in the art that the
surgical stapling instrument 9 and cartridge 1 are likely to assume
various positions wherein the staple feeding track 37 and the
staple forming track 24 are not vertically oriented and the passage
formed by window 55 is not horizontally oriented. Nevertheless, the
relative orientations of these elements with respect to each other
do not change.
Modifications may be made in the invention without departing from
the spirit of it.
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